Volume 207, January 2023, 111613
W.H. Peng a b c,S.Z. Hao c, W.T. Pan b, Z.B. Lv b, T.H. Fang a, L.M. Zhao
Abstract
Effects of primary WC size (DWC) in the surface enhancing of WC-Co cemented carbides by high current pulsed electron beam irradiation (HCPEBI) were studied in this work by investigating the morphological/microstructural evolution, phase transformations and the variation of microhardness of samples (Co: 10 wt %, DWC: ∼1.27 μm, ∼0.87 μm and ∼0.42 μm) treated with a range of HCPEBI shots under the energy density of 6 J/cm2. Results showed, with accumulating HCPEBI, the surface roughness of coarse-grained samples increased more significantly. The effects of DWC were more prominent in phase transformation and microstructure change under lesser irradiation. For samples with larger DWC, although the decomposition rate of WC in the top surface region was the lower, the amount of graphite precipitates prevailed overall. The maximum microhardness was also found in the irradiated coarse-grained (DWC = ∼1.27 μm) samples 3128.5 HV, showing a ∼80% increase from the initial state ∼1735.8 HV. Whereas for the fine-grained samples, surface microhardness gained a mere ∼29% increase after 35 shots.
Keywords
Cemented carbidesElectron beam treatmentSize effectsMicrostructuresSurface remeltingMicrohardness
